Twin Towers BUILD LOG

[kryptonitewhite 1]

OK Ricci, I get it now.. increased airspace increases low end output...not high end...on a sloping scale. So building super large requiring less power overall decreses high bass

output. So what if a gentle slope of 1dB/oct HP was used up high say around 30Hz to allow more power applied?

So we all knew it was a matter of time..just didnt expect an hour. The amp clipped bad probably due to bad house electrical, on music. I had to set the gain to 26 for decent

output for music any more and it clipped. But on movies even way down at 14 it bottomed the sub hard. So ya. I did it. I broke it already. alright? So anyway...tried to kill it

by blasting it at tuning... forgot I retuned to 11Hz so the 1st attempts were at 17Hz then last at 11Hz.

[kryptonitewhite 1]

so I got the best girl in the world.. i have 3 gal friends, but 2 have been fallin back on their word.. was supposed to get some help painting and picking blinds..but ya know, i

don't care about looks one bit...I care about the builds. This girl been getting her butt kicked helping unload wood and building. I had her cut the cone out for the recone, and

she said "shouish!" I'm a selfish pos.. she sliced/stabber herself right after I said it and blood squirted everywhere. The cut was deep...but she was a trooper. She refused

the hospital but i made her. No stitches, it was a big clean cut so it went back together nicely...put a strip on and sent us home. I owe this girl my life she done so much for

me.

So we get home and she picks the knife back u and says "now what?" so we finished cutting the cone off and went to bed

[kryptonitewhite 1]

Edited March 18, 2010 by kryptonitewhite

[kryptonitewhite 1]

1 complete less a port brace... and onto #2...

Edited March 19, 2010 by kryptonitewhite

[///M5 2,833]

Complete? A box that large, playing frequencies that low, really needs some serious bracing.

[kryptonitewhite 1]

Anyone want to guess what that other cut out line is for?

[kryptonitewhite 1]

[kryptonitewhite 1]

[kryptonitewhite 1]

[kirill007 52]

Holy crap that is HUGE.

Why didn't you just used infinite baflle instead of a huge box?

[kryptonitewhite 1]

[kryptonitewhite 1]

This is only going to cause more debate and more argument, but I'll try to explain my OPINION anyway. 1st problem: I am 99% concerned with 20Hz on DOWN only! But that statement will go nowhere with many. So for one plot I put a LOW PASS filter on the IB because I want more output from 10-20Hz and little output in comparison from 20Hz on up. 8 18's would be WAY overkill from 20Hz on up, but comparable to 20Hz on down with just 2 in my enclosures.I plotted to get as close to Xmax without exceeding as I could using SSF/HP filters on the vented boxes, and no filter on the IB allowing it to not exceed Xmax till 7Hz allowing electronics rolloff to take care of it real-world.

RED 125 cubs 13Hz HP 13Hz 1500 watts

GREEN 125 cubes 10Hz HP 10Hz 1100 watts

PINK 1111 cu ft sealed (IB) no HP, 1 pic with LP 10Hz 2700 watts (Fi rated them 550 watts to 20Hz, appeared correct, but I must be good to at least 10Hz)

One of the best pics doesnt always show up...bandwidth exceeded:

[kryptonitewhite 1]

2 problems 1 at a time: I have a 7.1 receiver, I run an HDMI from my Blu-Rey to the rceiver, but I only get 5.1. The rear speakers do not light up on the little map on the display, even when DTS is detected or True HD...nor is there any sound ever from the 2 rears

[///M5 2,833]

Your room, in particular now, is too small to bother with 7.1.

I assume this thread is a joke though anyways after seeing the bracing, obviously you aren't actually going to use those enclosures as is and will turn them into something else. You had me though.

[kryptonitewhite 1]

alright guys... I thought HD was all discrete 7.1

it is not. checked my movies, they are 5.1

[kryptonitewhite 1]

Now that I have the 7.1/5.1 figured out.. I thought HD was always discrete 7.1... owell moving along...

problem 2 is clipping. for movies, as expected, I have WAY too much power @ 40hms...which is why I ordered dual 4's... so I'll *only* have 3X the power I need at 8 ohms. But right now, with movies, the sub still has too much excursion with the gain only on 14... but for music I have to turn it up to 26 to get resonable output. At 26 the sub wants more, has plenty of room...but the amp starts clipping a touch above that. 2 more clicks and it clips HARD on higher frequencies but not lower. So is my electrical bad? I have RCA to XLR. I have the receiver sub maxed at +12.5dB.

So anyway, I no longer have my helper ( NOT my wife, NOT my girlfriend...a really nice gal..that is a friend of mine..I am just as unconventional in every other aspect of my life I don't have girlfriends or wives )

Now I know many people are gonna say "how about port support!" but I am not sticking with a 6.5Hz tune! Read the entire thread before posting! I need a 5" long port with a 12" sonotube in 125 cubic feet for a 15Hz tune! 5" port length! 10Hz I think was 17"... I am leaving 5" of overhang on the outside so that I have 2 free ends... 11.25" will be just fine...but I know I will hear just as much over that as I have over my bracing. and NO I am NOT bracing anymore than those 2 little 2x4's making that X... thanks for the ideas, thanks for the suggestions, but you can say I told you so after the box explodes.

um... didnt mean to upload these but may as well post... I overcaulk initially, always...owell... then after it cures I usually go back and put a 2nd layer in the corners and smear for extra support and air tight seal...then a 3rd. Only 1 extra layer this time...it will make it easier to finish pulling them apart after they implode due to lack of bracing.

also keep in mind, these 12" ports may be taken out and increased to 14" 16" or even 18" if they can't fully support 22's

[///M5 2,833]

Bracing isn't about exploding but taming the box. Going to have a craptastic response if you don't.

[kryptonitewhite 1]

i know resonating panels... most likely i wont even know it

[///M5 2,833]

It defeats one of your fundamental goals however making the whole box design dubious to say the least.

[Luke352 1]

i know resonating panels... most likely i wont even know it

And exactly what makes you imperviouse to hearing panel resonance.

Think about it!

You have very large unbraced area's which means there resonant frequency will be very low, down near your drivers passband. And due to how large the area's are that are unbraced, you have a massive radiating area, you could be deaf as a door post and you'll still hear those things flapping around.

[kryptonitewhite 1]

first vid 11Hz sine wave at a pretty moderate level, shakes the whole house and rattles windows in the opposite end of the house a little louder than the old box used to...but the old box did it at 18Hz, this is 11!

So then I do it again, but part way in I turn it up to at least 2.5" p-p maybe even 3"... they still have room to go... but my clip indicators are solid... no clipping... I was barely even pushing the amps... and the subs had zero complaints!

[bighitter 0]

first vid 11Hz sine wave at a pretty moderate level, shakes the whole house and rattles windows in the opposite end of the house a little louder than the old box used to...but the old box did it at 18Hz, this is 11!

So then I do it again, but part way in I turn it up to at least 2.5" p-p maybe even 3"... they still have room to go... but my clip indicators are solid... no clipping... I was barely even pushing the amps... and the subs had zero complaints!

FYI, if you are running optical or digital coaxial you will only get 5.1 at max, the newer 7.1 formats are only sent via HDMI digitally or already decoded via 7.1 analog output if your player has this output. But you are correct not all blu-rays are 7.1

Impressive build so far, more impressive is your lady helping.

Edited April 1, 2010 by bighitter

[kryptonitewhite 1]

first vid 11Hz sine wave at a pretty moderate level, shakes the whole house and rattles windows in the opposite end of the house a little louder than the old box used to...but the old box did it at 18Hz, this is 11!

So then I do it again, but part way in I turn it up to at least 2.5" p-p maybe even 3"... they still have room to go... but my clip indicators are solid... no clipping... I was barely even pushing the amps... and the subs had zero complaints!

FYI, if you are running optical or digital coaxial you will only get 5.1 at max, the newer 7.1 formats are only sent via HDMI digitally or already decoded via 7.1 analog output if your player has this output. But you are correct not all blu-rays are 7.1

Impressive build so far, more impressive is your lady helping.

thanks for the props big hitter! I'm runnin HDMI off a 7.1 sound card I just got and I had 4 ladies help :D

[kryptonitewhite 1]

the white trash redneck did it again.. the plan all along was a 14Hz tune, as 13Hz starts a slight dip and the dip just gets bigger as I tune lower. So WinISD plots at 14Hz are exactly what I want... flat flat flat till 15-16Hz starts to show the beginning of a HUGE spike at 14Hz. I'll snap a pic of the plots later..but anyway I retuned to my final 14Hz and played a 15Hz sine wave for a full minute at full excursion and didnt even get warm.

jordan powell

kryptonitewhite

[kryptonitewhite 1]